This is how the AstraZeneca vaccine works
Targeted for links to rare cases of thrombosis, it uses chimpanzee adenovirus as its platform
BarcelonaMarred by constant distribution breaches, changes in age criteria and now also dogged by its link to rare cases of thrombosis, the Oxford/AstraZeneca (UK) vaccine was approved for use on 29 January 2021 and the UK had already licensed it in December. The technology it uses - genetically modified attenuated virus, in this case chimpanzee adenovirus - has previously been used to produce vaccines against Ebola and Zika. It is the same mechanism of action as the Janssen and Russian Sputnik V vaccines. It is licensed in a dozen countries, although some have stopped vaccination after the cases of thrombosis.
- A genetically modified, attenuated virus, the non-replicating chimpanzee adenovirus, is introduced into the body as a platform that carries the S protein.
- The virus contains the genetic information for our cells to manufacture covid-19 virus proteins, such as the S protein.
- Our body recognizes this protein as foreign and produces antibodies and T-lymphocytes.
- If we become infected, the antibodies will block the virus and the lymphocytes will destroy the infected cells.
- The vaccine cannot cause disease from adenovirus or SARS-CoV-2.
- Indicated for: People aged between 18 and 69.
- In Catalonia it is now administered to: People between 60 and 69 years old. Before the European Medicines Agency (EME) linked it to rare cases of thrombosis, the so-called essential groups (teachers, police, firefighters, and so on) up to 55 years of age had been vaccinated.
- It is contraindicated for: People with severe hypersensitivity to any previous dose or any of the components.
- Pregnancy: As there are not enough studies in pregnancy, it is also not recommended for pregnant women, although there are no indications of safety concerns. For pregnant women who are in a group where vaccination is recommended, e.g. healthcare workers, vaccination can be considered according to the benefit/risk assessment.
- Vaccination should be postponed in case of: Having a severe acute illness, but not in case of having a mild illness without fever.
- It is not recommended in: In patients with severe immunosuppression, uncontrolled cardiovascular, hepatic, renal, renal, metabolic, endocrine and severe neurological diseases there are no consistent data available and the use of other vaccines is recommended.
- If the age limit is not lifted, it is also not recommended for people over 70 years of age.
- Storage: It is stored at a temperature between 2 and 8 degrees, has a life of up to six months and should not be frozen or diluted.
- Administration schedule: Two doses are administered with an interval of between 10 and 12 weeks (between 70 and 84 days).
- Efficacy: It offers 81.3% protection against covid after the second dose.
- Cost: The approximate cost per dose is of 2 euros.
- The most frequent are: Pain at the injection site, fatigue or tiredness, headache, chills, nausea, joint pain and fever.
- Intensity: Most are mild or moderate in intensity and disappear after a few days.
- Side effects: The European Medicines Agency (EME) has concluded that thrombi may be a side effect of the AstraZeneca vaccine in "very rare" cases but recommends continuing vaccination, arguing that the benefits outweigh the risks.